Illegal temporary surface surcharge can induce additional ground stress

which may cause adverse effects or damage to the existing shield tunnel structure. However

current methods for predicting tunnel longitudinal responses to surface surcharge generally simplify the tunnel as an Euler-Bernoulli beam resting on Winkler foundation

which ignores the shearing deformation of shield tunnel and cannot consider effect of the burial depth on the coefficient of subgrade reaction. In this study

a new analytical method is developed to evaluate the existing shield tunnel deformation subjected to surface surcharge

considering the tunnel shearing effect and the burial depth of the tunnel. In the proposed method

the shield tunnel is treated as Timoshenko beam resting on Winkler foundation and the effect of burial depth of shield tunnel on the coefficient of subgrade reaction is considered. The effectiveness and feasibility of the proposed method is verified by a three-dimensional finite element analysis and measured data from a case. Parametric analysis indicates that a shallowly buried shield tunnel suffers large settlement when the distance between the load center and tunnel axis is relatively close. Increasing the equivalent bending stiffness and the coefficient of subgrade reaction would remarkably reduce tunnel settlement. The tunnel settlement was hardly sensitive to equivalent shear stiffness. However

increasing equivalent shear stiffness would significantly reduce the dislocation between the adjacent rings. In general

the proposed method will serve to be theory support for reasonably predicting the shield tunnel responses to surface surcharge.